whirlpool duet powers up but will not start

washer will allow me to select a cycle seems ready to start but will not lock door and start wash.

Unfortunately this can be several things, including the door lock and main control board. I think it is the door lock, but look under the top cover or inside the lower service panel for tech notes that will tell you how to put it into test mode and generate error codes that may (or may not) help determine the problem.